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Summer Globes by Elisabeth Ginsburg

Gardens and globes go together.  Beginning in spring and progressing through the growing season, the purple or white globes of various allium species stand tall. Annabelle-type hydrangeas are prized for their large, globular flowerheads.  Formal gardens boast shrubs clipped into tight lollipop shapes, and retro gardeners decorate with old-fashioned gazing globes.

Given the enduring allure of rounded shapes, it is no wonder that perennial globe thistle, or echinops species have long been fashionable.

As is often the case in horticulture, the common name, “globe thistle,” is a misnomer.  The flowers are definitely globe-shaped, but echinops are not a thistle at all.  Despite its membership in the vast Compositae or daisy plant family, the blooms are not daisy-like. To add to the general confusion, globe thistles bear ferocious-looking gray-green foliage on lanky stalks, with leaves that look like the result of an aggressive dandelion/thistle mash-up.  Fortunately, their forbidding appearance only marks them as tools in the arsenal of deception that Mother Nature uses to make gardeners’ lives interesting. The prickles are not particularly lethal, and the undersides are soft, touchable, and light-colored.

The “globes” that give globe thistle its name are actually orbs of individual tubular flowers clustered into tight, round shapes. Some of the most common are ping pong ball-size, but the flowerheads may be smaller or larger depending on species and variety. White globe thistles are available commercially, but the blue-flowered varieties are most common and range in tone from powder blue to a rich, dark shade.  The blooms may also have a sweet fragrance.

Add globe thistles’ virtues together, and you come up with tough, perennial performers that make great garden exclamation points. Depending on the size of your beds or borders and the variety you choose, they generally work best at the middle to back of the border.

If you are a container gardener, you can grow echinops as a stand-alone specimen, or as the “thriller” in a “thriller/filler/spiller” arrangement in a large container.  The plants will be perfectly happy, even if you occasionally miss watering them.

Like their common thistle namesakes, echinops are summer plants, shining from July through September. The flowerheads dry intact on the stalks and make excellent everlasting specimens for indoor arrangements. If you want to speed the drying process and preserve color, pick the stems while the flowers are blooming and hang them upside down in a cool, airy place until they are thoroughly dried.

Several echinops species dominate the retail market, including Echinops ritro, the small globe thistle. “Small” refers to the relative width of the flowerheads, not the plant’s overall size. One of the best ritro varieties is the English-bred favorite, ‘Veitch’s Blue’, with blue-purple flowers on plants that grow up to four feet tall and two feet wide. Another ritro variety, ‘Platinum Blue’, grows up to 36 inches tall, with bright blue-purple blooms. Echinops bannaticus, the “blue globe thistle”, is another tall plant, native to Romania. ‘Blue Glow’ is a bannaticus variety, featuring steely blue flowerheads. ‘Taplow Blue’, also a bannaticus, boasts steel-blue globes on four to five foot stems. Some merchandisers also offer Echinops sphaerocephalus, known as the “great globe thistle”. Pair any of the blue echinops with the white-flowered sphaerocephalus ‘Arctic Glow’, which is a little shorter, but provides great color contrast. Shorter still is the equally white-flowered ‘Star Frost’.

Globe thistles prefer sunny conditions, but will perform in light shade, and actually do best in lean, well-drained soil. Amend heavy clay with sand or grit to ensure that necessary drainage.  While the plants don’t like desert conditions, they do not need the constant moisture and fertilizer fixes demanded by other summer bloomers like annuals and roses.

“Echinops” is from the Latin word meaning “hedgehog”. Most likely the great plant taxonomist Linnaeus thought the flowerheads looked a little like blue versions of the small animals.

Echinops are in bloom in July, along with many of their daisy family relations.  More flowers will appear as the summer progresses, aided by deadheading or cutting stems for fresh or dried arrangements.

Good local garden centers may have some plants on the pallets. If not, check specialty nurseries online, where choices abound.

About Elisabeth Ginsburg

Born into a gardening family, Elisabeth Ginsburg grew her first plants as a young child. Her hands-on experiences range from container gardening on a Missouri balcony to mixed borders in the New Jersey suburbs and vacation gardening in Central New York State. She has studied horticulture at the New York Botanical Garden and elsewhere and has also written about gardens, landscape history and ecology for years in traditional and online publications including The New York Times Sunday “Cuttings” column, the Times Regional Weeklies, Horticulture, Garden Design, Flower & Garden, The Christian Science Monitor and many others. Her “Gardener’s Apprentice” weekly column appears in papers belonging to the Worrall chain of suburban northern and central New Jersey weekly newspapers and online at http://www.gardenersapprentice.com. She and her feline “garden supervisors” live in northern New Jersey.

Summer Blooming Trees by Elisabeth Ginsburg

Spring in most gardens is shot through with horticultural fireworks as flowers burst up from the soil, the trees and shrubs flash bright green and growth moves forward at warp speed.  In summer all of that action slows down, allowing gardeners to catch up (at least theoretically).

Usually the glories of the summer ornamental garden are most evident in colorful annuals, like zinnias, snapdragons, sunflowers, and the like.  But color may also come from on high, as summer flowering trees make a splash in late June, July, August, and the first warm weeks of September.   Choose one or more of them to draw the eye upwards and provide delight during the year’s warmest and longest days.

Draped in Crapes

“Crape myrtle” is often misspelled as “crepe myrtle”, an easy mistake that sometimes confounds spell-checkers. Spelling issues aside, crape myrtles, long a staple in southern gardens, have moved northward as the result of breeding advances.  Depending on variety, the plants are hardy in USDA plant hardiness zones 6 through 9.

The most common crape myrtles in commerce are varieties or hybrids of Lagerstroemia indica, which is native to parts of Asia, including China, Indo-China and Japan.  Some have shrubby habits, but most are grown as small trees, topping out anywhere from eight to about 25 feet, depending on variety. In mid to late summer, those trees sport lush flower panicles  made up of scores of individual six-petaled blooms in shades including white, a range of pinks and roses, dark red and lavender.

To add to its other virtues, crape myrtle is a multi-season performer.   Most varieties have smooth grayish bark that exfoliates or peels off to reveal underbark that may be brown, gray or even pinkish. The effect is like elegant camouflage and is starkly beautiful in the winter when the branches are bare.
To add to the four-season equation, crape myrtle leaves, which are oblong and appear in groups of three, tend to be smooth and glossy, coloring up in the fall in shades of red, orange and yellow before leaving the scene for the winter.

Crape myrtles like the same conditions as roses—full sun for at least six hours per day. If your chosen site receives a little less light, the tree or shrub may still thrive but will likely produce fewer flowers. Plant in holes filled with good commercial potting mix, like Fafard® Ultra Outdoor Planting Mix and mulch thoroughly. Water regularly to establish a strong root system.
A Rose is a Sharon

Roses of Sharon (Hibiscus syriacus) are nothing new on the American scene.  They were first documented by John Custis, a relative of Martha Washington’s first husband, in 1736.  They have been fixtures in nursery catalogs since nursery catalogs began, and remain popular to this day.

Hardy in USDA Zones 6 through 8, the small trees or large shrubs (growing anywhere from 8 to 12 feet tall) bloom any time from June through early October, depending on local climate conditions and variety.  The season of bloom tends to be long.  Flowers last only a single day, but the buds open in succession, so the plants look opulent over a period of weeks.

 Roses of Sharon flowers may be single or double-petaled.  Single varieties feature hollyhock-like flowers in either white, pale pink or pale blue-purple, many with red central “eyes” surrounding a yellow stamina column.  Doubles come in the same colors, but no “eye” is visible due to the plethora of petals that make the flowers look like frothy puffs.  One thing is sure—well-tended specimens are beautiful in bloom.

The main drawback of old-fashioned rose of Sharon varieties is that they self-seed prodigiously.  Avoid this by shearing the plants right after they flower.  Newer varieties tend to be sterile, allowing gardeners the luxury of not worrying about grubbing out scores of little hibiscus seedlings.

To say that rose of Sharon is not fussy about soil is an understatement, though they do best in sunny spots.  The plants are impervious to varmints and heavy clay soil, and will even succeed near black walnut trees.

Tea Family Trees

Franklinia, Gordonia and Stewartia are closely related small trees belonging to the Theaceae or tea family.  All shine in mid to late summer, bearing white, camellia-like flowers, most with central bosses of golden stamens.

The stewartias include Japanese stewartia (Stewartia pseudocamellia), hardy in USDA zones 5 through 8,which blooms in mid-summer and may grow anywhere from 20 to 40 feet tall,  The trees feature dark green, ovoid leaves that color up nicely in fall, as well as colorful, exfoliating bark that provides winter interest.

The smaller mountain stewartia (Stewartia ovata) is native to the southeastern United States, and bears the same lovely flowers as its Japanese cousin, but on trees that grow 10 to 15 feet tall.  It is hardy in USDA zones 5 though 9. While lacking the exfoliating bark of the Japanese stewartia, it does provide fall color.

Stewartia thrive best in full sun to very light shade (in locations with hot, humid summers), and well-drained soil.  Mountain stewartia might also succeed in a large container, with adequate drainage and consistent moisture.

Tales of Franklinia

Sometime in 1765, American botanist John Bartram and his son, William, were prowling through what is now the state of Georgia in search of new and unusual plants.  Near the banks of the Altamaha River in southeastern Georgia, they found a group of interesting trees or large shrubs with white, camellia-like flowers.  They collected seeds and grew them on at their Philadelphia nursery.  The new species was christened Franklinia alatamaha, in honor of the Bartrams’ friend, Benjamin Franklin.

Franklinias, which are hardy in USDA Zones 5 through 8, stand between ten and twenty feet tall, with a spread of 6 to 18 feet and an upright, spreading habit.  The long leaves are roughly oval-shaped and glossy.  Green in summer, they turn orange-red in fall, remaining on the trees for a relatively long time.  Franklinias bloom in mid to late summer, bearing flowers that are at least three inches across with white petals and prominent golden stamens in the middle.  Rounded, woody fruits follow the flowers.

The Franklinia tree was never again sighted in the wild, so all existing specimens are descended from Bartram’s original seedling trees.  Because the gene pool is limited, plant breeders have crossed the Franklinia, with closely related species to inject new genetic material into the pool.  Eventually through the process of crossing and back crossing the offspring, breeders hope to produce a strong new Franklinia.

One of the related species crossbred with Franklinia was the native loblolly bay (Gordonia lasianthus), which is not readily available in commerce, and bears similar camellia-like blossoms.   The resulting evergreen hybrid was given the trade name ‘Sweet Tea’ , but it is known botanically as xGordlinia grandiflora.

‘Sweet Tea’ is hardy in USDA Zones 7 through 9, grows up to thirty feet tall, with a narrow, eight-to-15-foot width.  It features fragrant white blossoms with petals longer than those of either the Franklinia or loblolly bay.  Though the fall color is not as pronounced as that of the deciduous Stewartia or Franklinia, the evergreen leaves redden at the end of the growing season.

 

About Elisabeth Ginsburg

Born into a gardening family, Elisabeth Ginsburg grew her first plants as a young child. Her hands-on experiences range from container gardening on a Missouri balcony to mixed borders in the New Jersey suburbs and vacation gardening in Central New York State. She has studied horticulture at the New York Botanical Garden and elsewhere and has also written about gardens, landscape history and ecology for years in traditional and online publications including The New York Times Sunday “Cuttings” column, the Times Regional Weeklies, Horticulture, Garden Design, Flower & Garden, The Christian Science Monitor and many others. Her “Gardener’s Apprentice” weekly column appears in papers belonging to the Worrall chain of suburban northern and central New Jersey weekly newspapers and online at http://www.gardenersapprentice.com. She and her feline “garden supervisors” live in northern New Jersey.

Hardy Geraniums for Shade by Elisabeth Ginsburg

Gardeners sometimes curse the shade.  At first glance, every desirable plant in the garden center seems to require at least six hours of direct sunlight per day.  But shade can also be a blessing.  It not only keeps you cool as you pull weeds and spread mulch, but can support plants that provide color, interest, and lovely flowers.

The hardy geranium or cranesbill clan is home to many garden stars, with shade-tolerant species and varieties abounding.  Breeders have gotten wise to increased public demands for tough plants that thrive in less light and are working hard to develop even more of them.

Hardy Geraniums 101

What is a hardy geranium, and how does it differ from the annual geranium plants that adorn pots, plots and window boxes throughout the growing season?

Those bright red “window box” geraniums are members of the Geraniaceae genus, but are known botanically as pelargonium, a category that includes scented-leaf, trailing (ivy), and fancy-leaf types.  In cold winter climates, most are grown as annuals, though some gardeners overwinter choice specimens indoors.

Hardy geraniums also belong to Geraniaceae, but are perennials, returning year after year.  They do not boast the big, fluffy heads of some of their pelargonium relatives, but bear lovely, five petaled flowers in shades ranging from pure white through pinks, roses, blues, blue-purples and near-black, sometimes with contrasting veins on the petals.  Most have lobed or incised leaves that are attractive even after the flowers fade, as well as seed capsules that resemble cranes’ bills, giving rise to the nickname. Hardy geraniums are useful for all kinds of growing situations, from rock gardens, to containers, to traditional garden beds. Many commercially available varieties are tolerant of at least light shade, but a special group of plants are especially appreciative of shady situations.

Fabulous phaeum

The largest category of shade-tolerant cranesbills is Geranium phaeum.  Hailing originally from Europe, Geranium phaeum is made for shade, preferring lower light and humus-rich soil.  The growth habit is sprawling, with plants rising to a height of about 18 inches and a spread of 24 inches.  The species’ petals are generally a dark purple to purple-black shade, which accounts for the old-fashioned nickname, “mourning widow”.  The word “phaeum” refers to the flowers’ dusky appearance.

But not all phaeums are as dark.  The popular ‘Samobor’ variety features flowers that have deep red tints, as well as alluring dark red blotches on the sharply lobed leaves.  Abandon mourning all together and indulge in brightness with the graceful white-flowered ‘Album’.  Another pale-flowered variety is ‘Langthorn’s Blue’, which features petals of palest blue, edged in darker tones, and complemented by splotched leaves, similar to those of ‘Samobor’.  Bred in Great Britain, ‘Alec’s Pink’ is dark rose-pink and not a bit somber.

A Jolt in the Shade

If you are looking for a shade garden wake-up call, try Geranium maculatum ‘Espresso’.  The large, mounding leaves are chocolate brown, contrasting nicely with the pink flowers.  Discovered in Pennsylvania, it is a good choice for the shaded parts of native plant gardens.  Other maculatums, like the pink-flowered ‘Beth Chatto’, and ‘Purpureum’, clad in purple petals, are also shade tolerant, but sport green leaves.

Hello Gorgeous!

Geranium nodosum ‘Clos de Coudray’ is a recent discovery from France, and it is gorgeous.  The typical five-petaled flowers of this “knotted cranesbill” are deep blue-purple with pale edges and deeper purple striations.  The flowers show up from June through October, but even when the plants are not in flower, the dark green, lobed leaves shine and color up in the fall.  Showing good tolerance for both shade and chilly weather, ‘Clos de Coudray’ is also perfect for containers at 15 inches tall and 18 inches wide.  Other members of the nodosum species are also shade tolerant, including ‘Whiteleaf’, with flowers similar to those of ‘Clos de Coudray’, plus maroon shading at the base of each petal.

Woodland Wonders

The woodland cranesbill, or Geranium sylvaticum is a natural for semi-shaded areas, having originated in wooded areas of Turkey and Europe. Try ‘Birch Variety’, with petals of deep blue purple surrounding white central “eyes”.  For added brightness and large white flowers try ‘Imaculee’. Another large-flowered sylvaticum is ‘Angulatum’, with big pink blooms.

Elegance in the Shade

For real elegance and impact, it is hard to beat Geranium versicolor.  The lobed, blotched leaves have a soft, hairy feel, but the flowers steal the show.  Each notched petal is white with prominent red-purple veins.  Its sibling, Geranium versicolor ‘Snow White’ features the same blotched leaves, but they accent pure white flowers.

Cranesbills for shade are at once delicate and tough, right for a wide variety of garden or container situations.  Most require consistent moisture and loamy soil.  If your soil doesn’t quite fit that description, amend it with Fafard® Premium Natural and Organic Compost.

Local garden centers generally carry only a few hardy geranium varieties, and often ‘Samobor’ is the only available shade option.  However, the internet abounds with possibilities.  The versatile plants—which are also deer and rodent resistant—are worth the search.

 

About Elisabeth Ginsburg

Born into a gardening family, Elisabeth Ginsburg grew her first plants as a young child. Her hands-on experiences range from container gardening on a Missouri balcony to mixed borders in the New Jersey suburbs and vacation gardening in Central New York State. She has studied horticulture at the New York Botanical Garden and elsewhere and has also written about gardens, landscape history and ecology for years in traditional and online publications including The New York Times Sunday “Cuttings” column, the Times Regional Weeklies, Horticulture, Garden Design, Flower & Garden, The Christian Science Monitor and many others. Her “Gardener’s Apprentice” weekly column appears in papers belonging to the Worrall chain of suburban northern and central New Jersey weekly newspapers and online at http://www.gardenersapprentice.com. She and her feline “garden supervisors” live in northern New Jersey.